China's deep coalbed methane resources have enormous potential. As a clean and high-quality energy, it is of great significance to ensure China's energy security and green and low-carbon development. The development of middle-shallow coalbed methane in China has basically been industrialized, but the development scale is far from the national planning goal. With the new progress made in the exploration and development of deep coalbed methane in recent years, it has provided new impetus for the rapid development of the coalbed methane industry. But when it comes to deep exploration and development, it faces a series of new geological, engineering, and other challenges that need to be tackled. In view of this, based on the latest national oil and gas resource evaluation data, the current situation of coalbed methane exploration and development in China was summarized, and the latest progress in deep coalbed methane exploration and development in typical blocks in China was evaluated. The new breakthroughs in geological evaluation, drilling, fracturing, and extraction of deep coalbed methane in recent years were summarized, and it is pointed out that there are problems in the current exploration and development of deep coalbed methane in China, such as low resource evaluation level, low adaptability of key technologies, and few mature demonstration projects that can be promoted and referenced.On this basis, four countermeasures and suggestions for the development of deep coalbed methane industry were proposed: strengthening resource exploration, strengthening key technical research, speeding up the construction of high-efficiency development demonstration zones, strengthening the co-exploration and co-exploitation of deep coal measures gas, so as to provide reference for promoting the exploration and development of deep coalbed methane in China.

The development of a high-grade waterway network in the Upper Yangtze River will play a crucial role in promoting the economic and social development in the Chengdu-Chongqing region. Waterway improvement through underwater blasting to removal the obstructing rocks is still one of the most effective method in mountainous river management, but its impact on aquatic organisms, particularly on passively drifting fish eggs and larvae, has raised significant ecological concerns. Long-term observational data of drifting larvae in the Upper Yangtze River were analyzed, focusing on their temporal distribution patterns and spatial variations in species composition and abundance. The propagation mechanisms of underwater blasting shock waves were examined, and the primary factors affecting shock wave intensity were identified. Current research on blast-induced fish damage was reviewed, with special attention paid to the effects of shock waves on eggs and larvae. Based on the documented drift patterns of eggs and larvae and the characteristics of shock waves, comprehensive ecological protection measures were proposed. These measures included temporal and spatial avoidance strategies, optimized blasting techniques, and the use of bubble curtain technology. These findings provide valuable insights for achieving sustainable development that balances waterway construction with ecological conservation in the Upper Yangtze River.

In order to investigate the heat and mass transfer of liquid droplet impinging on a heated surface with different wettability, VOF(volume of fluid) numerical simulation method was used to analyzed the mechanisms of wall wettability and surface temperature on droplet morphology and heat transfer characteristics. The results show that the hydrophilic wall is favorable for droplet spreading, while the hydrophobic wall is favorable for droplet rebound. With the increase of contact angle, the maximum spreading factor of droplets decreases, the time to reach the maximum spreading factor is shortened, and the average heat flux of the wall surface decreases. Surface temperature has less influence on the droplet spreading stage, with the increase of surface temperature, the droplet phase transition rate accelerates, the average heat flux of the wall surface increases, and the Leidenfrost phenomenon occurs when the surface temperature exceeds the critical temperature.

Clouds play a crucial role in the atmospheric dynamics of the Earth, and precise segmentation of ground-based cloud images is essential for improving the accuracy of weather forecasting. In response to issues such as varying data quality, low data volume, and different capture angles in existing open-source cloud image datasets, a labeled standard ground-based cloud image dataset (Cloud-GT) was constructed using manual annotation and transfer learning methods. The color channel component threshold segmentation method was employed to eliminate sunlight interference. Furthermore, an improved U2Net-based ground-based cloud image segmentation technique was proposed. The model introduced channel attention modules and depth-wise separable convolution modules in the feature extraction unit, which greatly reduces the network model parameters while improving the effective feature extraction of ground-based cloud maps within the network. Finally, comparing and analyzing the method with classical segmentation networks, experimental results indicated that the method achieved classification pixel accuracy, mean class pixel accuracy, average intersection over union, intersection over union, and F₁ score of 84.03%, 90.88%, 84.13%, 74.12%, and 89.59%, respectively. In comparison with U2Net, UNet, and FCN, the method demonstrated a significant improvement in performance. In conclusion, the method not only substantially reduced the model parameters but also effectively enhanced segmentation accuracy, which provides the possibility of practical application.

In the southern Great Xing'an Range, the Xishala area exposes a substantial amount of Mesozoic strata of Xinmin Formation (J₂x) and Manketouebo Formation (J₃m). However, due to the presence of rhyolite in the rock association, it is easy to confuse the stratigraphic division and lead to disputes of the stratigraphic attribution of rhyolite. Therefore, zircon U-Pb dating and geochemical characteristic analysis of the rhyolites were conducted, and stratigraphic sections of the Xinmin and Manketouebo Formations were compared to explore the formation age, tectonic setting, and stratigraphic attribution of the rhyolites. The results indicate that the geochemical characteristics of the riolites in Xishala area are high SiO₂ content (The value of mean is 75.74%.), rich alkali content [mean(Na₂O+K₂O)=7.69%] and low Mg and Ca content, belonging to peraluminous and high-K calc-alkaline series. The Chondrite-normalized REE pattern is right-dip type, with relative enrichment of LREE and relative depletion of HREE, the value of (La/Yb)_Nis between 10.61~14.21 and strong negative Eu anomaly (The value of δEu is between 0.44~0.53.). LILE(large ion lithophilic elements) such as Rb, Ba and K are relatively enriched, while HFSE(high field strength elements) such as Nb, Ta and Ti are relatively depleted, indicating that the magma originated from crustal materials. The LA-ICP-MS zircon U-Pb dating results show that the age of the rhyolite is (167.7±2.6) Ma, belonging to the Middle Jurassic, and it formes in the extensional tectonic action after the closure of the Mongolian-Okhotsk ocean. Based on the comparative study of regional geology and sectional rock assemblage types, the rhyolite belongs to the Manketouebo Formation.

The Kezirto pluton is located in the alkaline intrusive rock belt on the northern margin of the Tarim Basin. The lithology is alkaline granite. The petrogeochemical characteristics were studied in detail. The U-Pb isotope age of the pluton was measured by LA-ICP-MS method, which provides a basis for the study of the characteristics, age, genesis and formation environment of the pluton. At the same time, the nature of late Paleozoic magmatic activities and their tectonic settings in the area were studied, which can better guide the exploration work in the area and have important theoretical and practical significance. The Kezirto granite pluton was divided into two parts, north and south. The total rare earth element content is relatively high. The ∑REE of the northern pluton was 261.723×10^-6~834.783×10^-6, and the ∑REE of the southern pluton is 422.174×10^-6~575.86×10^-6. HFSE(high field strength elements) are obviously enriched relative to LILE(large ion lithophile elements), and elements such as Ba, Sr, P, and Ti are obviously depleted, with obvious negative Eu anomalies. The chondrite-normalized rare earth element diagram shows a slightly right-inclined seagull-like shape, and light rare earth elements are slightly enriched compared to heavy rare earth elements. The Kezirto pluton is A1-type granite. The LA-ICP-MS U-Pb isotope ages of the north and south plutons are (273.8±2.9) Ma and (274.8±1.8) Ma, which are contemporaneous plutons. The formation of the Kezirto pluton is due to the underplating of mantle-derived magma, which leads to the remelting of ancient rocks in the lower crust. After that, it undergoes fractional crystallization. During the formation process, it is contaminated by the crust to different degrees. The pluton has experienced the tectonic environment of deep mantle plume and intracontinental rift.

In recent years, important progress has been made in the lithologic trap exploration of the Lower Cretaceous Yageliemu Formation in the Yakela fault convex and its surrounding areas in the Tarim Basin, in order to clarify the sedimentary facies distribution law of the clastic rock reservoir of Yageliemu Formation in this area, and promote the efficient exploration and development of the clastic rock reservoir. Based on an integrated analysis of core samples, well logging data, and 3D seismic surveys, the sedimentary facies types and spatial distribution patterns of the Cretaceous Yageliemu Formation in the Yakela fault convex and its surrounding areas in the Tarim Basin were investigated. Furthermore, under the framework of source-to-sink system theory, the controlling effects of source area characteristics on fan delta development were systematically examined. The results show that fan delta group deposits are developed in the Yageliemu Formation in the Yakela fault convex and its surrounding areas. During the deposition period of the Yageliemu Formation, the ancient uplift in the Yakela fault convex area was obviously segmented, with a banded uplift in the NEE direction, with two bulges in the east and west, and a low terrain in the middle. Based on the analysis of source-sink system, it is clear that the sediment source of the fan delta group is from the weathered denudation area of the ancient uplift, and the multi-branch ancient gullies provide sediment transport channels for the fan delta Group. It can be seen that paleogeomorphology and gully development characteristics control the sour-sink system of Yageliemu formation in the Yakela fault convex and its surrounding areas, forming a sedimentary pattern with multiple sources supply. The western ancient uplift is mainly characterized by high uplift and large gully area,the eastern section is mainly characterized by low uplift and small gully area. The development scale of gullies in provenance area controlled the distribution scale of deltaic sediments around ancient uplift. The gentle slope fan delta sedimentary system developed in the south of the ancient uplift, and the steep slope and gentle slope fan delta sedimentary system developed in the north. The analysis of source-sink system reduces the uncertainty of sedimentary facies study of Yageliemu Formation and can provide more geological basis for oil and gas exploration.

Tahe Oilfield was one of the important oilfields in western China. The monitoring and development of remaining oil reserves were paid significant attention to and were regarded as one of the current challenges in oil and gas exploration and development. Well-to-surface time-frequency electromagnetic detection technology, due to its sensitivity to oil-gas-water interfaces, was increasingly applied in oilfield development. However, as time-frequency electromagnetic detection technology was introduced relatively late in oil and gas detection, the related detection mechanisms and high-resolution signal extraction and interpretation were still under research. Through the analysis of well-to-surface time-frequency electromagnetic exploration principles, a technical sequence for differential apparent resistivity, differential phase processing, and imaging analysis of well-to-surface time-frequency electromagnetic data was established, starting from the definition of regional apparent resistivity. The differential processing results of time-frequency electromagnetic data collected from the actual production well TX1 in Tahe Oilfield demonstrated that the high-density sampling provided by multi-pole transmission and multi-frequency reception of well-to-surface time-frequency electromagnetic detection technology offered high-resolution reservoir detection datasets. The new differential data processing technology could greatly enhance the effective identification capability of deep oil-gas-water interfaces. The successful trial of this method provided a promising technical means for oil-gas-water detection in oilfield development. Additionally, through comparative analysis with seismic exploration results, it was found that well-to-surface electromagnetic exploration had unique advantages in identifying complex underground structures and could provide complementary information to seismic exploration.

ABR(auditory brainstem response) is an objective method for detecting hearing loss, which is widely used in clinical practice, and its waveform characteristics are influenced by stimulus parameters. There are stimulus artifacts in ABR measured using unipolar stimulus, and alternating polarity is currently the only way to eliminate stimulus artifacts. However, considering the physiological differences in the effects of stimuli with different polarities on the auditory system, alternating polarity stimuli may lead to latency jitter in the induced ABR. Therefore, a new method was proposed to eliminate stimulus artifacts-the method of division and sum polarity, which first used positive and negative stimuli separately and then superimposed the two responses induced. The subjects with normal hearing were recruited, and their data that the click ABRs under four polarity ways (positive polarity, negative polarity, alternating polarity, division and sum polarity), as well as the tone-burst ABRs at five frequencies under two polarity ways (alternating polarity and division and sum polarity) were compared, with a focus on their waveform differentiation and latency differences. The results show that the difference in click ABRs under different polarity ways is insignificant, indicating that it is not sensitive to stimulus polarity. The waveform of low-frequency tone-burst ABRs is better under division and sum polarity than under alternating polarity, indicating that the low-frequency tone-burst ABR is more sensitive to stimulus polarity, and the sensitivity decreases with the increase of stimulus frequency. Based on the analysis of the above results, it is recommended to use unipolar stimulus for the click ABR, and the division and sum polarity method for the tone-burst ABR. The feasibility of the division and sum polarity method is validated in this study, which provides a new approach for eliminating stimulus artifacts when measuring evoked potentials.

In response to problems of rapid excavation of deep shafts, such as lining cracking and high support costs, based on the engineering background of -906~-1 158 m section of an overseas copper and gold mine, the support parameters of shaft were studied by theoretical calculations, numerical simulations and field tests. In order to restrict deformation of the shaft and reduce the cost of support reasonably and effectively, a shaft model was established based on the engineering practice, the stability of surrounding rock with the different parameters was analyzed by FLAC^3D numerical software combined with fluid-structure interaction. The results demonstrate that for the class Ⅲ surrounding rock, “anchor net spraying+steel fiber concrete” support is adopted, and its parameters are as follows: bolt diameter 22 mm, length 2.3 m, shotcrete thickness 50 mm, row spacing 1 m×1 m, steel fiber concrete thickness 550 mm. For the locally existing class Ⅳ~Ⅴ surrounding rock, “anchor net spray+foam board+steel fiber concrete” support was proposed, and the thickness of buffer layer foam board is 100 mm, and the thickness of steel fiber concrete is 600 mm. Field test results show that the average convergence rate of surrounding rock is 0.18~0.31 mm/d after 412 h excavation, which meets the requirements of air inlet shaft construction, and the construction efficiency is improved by about 23.5% compared with the domestic deep shaft. This work can provide a guidance for the support design of shaft in soft-fractured strata with water-rich.